<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    new Promise((resolve, reject) => {
      resolve(1)
      new Promise((resolve, reject) => {
        resolve(2)
      }).then(data => {
        console.log(data) // 2
      })
    }).then(data => {
      console.log(data) // 1
    })
    console.log(3)
  </script>
</body>

</html>